Revealing mistake: At the zoo, Harry looks to his right, at the 'bred in captivity' sign of the Python. In this close-up, the green plant that is below, to the side of the exhibit sign, is protruding out past where the glass supposedly is, yet this is BEFORE the glass disappears. As a matter of fact, this plant, nearest the exhibit sign, changes its position considerably throughout these shots. (00:06:50)
Revealing mistake: In the scene at the beginning of the movie where all of the letters from Hogwarts are coming into the Dursley's house, it causes everything to shake. It is quite obvious, however, that it is just the cameras that are moving as no objects in the room are moving at all (ie. the curtains, or any of the knicknacks). (00:11:30)
Revealing mistake: When Harry is walking in the library's restricted section, you see the shadow of the library pillars on the bookshelf. If the light was coming from his lantern, there would be no shadow - the light is obviously from a spotlight elsewhere. (01:25:20)
Revealing mistake: In the shots facing Vernon, he holds the first Hogwarts letter while sitting at the table. Though in the close-up of the letter as he holds it, it is not Richard Griffiths' hand, that is shown with bitten up fingernails, holding the envelope. (00:09:15)
Revealing mistake: While Vernon kneels as he tosses Harry's Hogwarts letters into the fire, the interior solid back of the fireplace is visible behind the flames. On Sunday, the first letter (from the fireplace with a CG back) hits Vernon in the face as it flies by. In the following two shots of the fireplace, as more letters fly out, there are now large holes at the interior back of the fireplace that are visible. As the letters pour down from above, air is blown through these holes to blow the letters out and about. (00:10:20 - 00:11:20)
Revealing mistake: Just after Harry gets back on his broom, the Slytherine seeker chases the snitch and he passes towers of (in order) Gryffindor, Hufflepuff, Ravenclaw, Slytherine, Gryffindor and Hufflepuff, on his left (this means Hogwarts is also to his left), when Harry flies up beside him. However, next shot as Harry slams into him, they still fly in the same direction, and the school is now on their right. Mistake with the background plate. (01:22:00)
Revealing mistake: When the mail comes, Ron receives the Daily Prophet and Harry asks, "Can I borrow this?" As Harry asks to borrow the newspaper, the Malfoy body double is plainly visible over Ron's left shoulder. (00:54:10)
Revealing mistake: After Madame Hooch takes Neville to the hospital wing, Malfoy takes the Remembrall and mounts his broomstick, on a convenient protruding metal rod. Then when he comes around, though the students step away and watch as he begins to fly off, many of their eyes are not level with Malfoy, as he is merely edited into the end of this shot. (00:57:50)
Revealing mistake: When Harry brings Ron to see the mirror of Erised, the green side of the invisibility cloak is seen when they are running to the mirror, near the door they entered from. (01:33:55)
Revealing mistake: In the flying letters scene, when the letters are coming through the chimney, if you look closely when Harry catches one you can see that the letters are all photocopied because the letter seal is not raised. (00:11:05)
Revealing mistake: During the Quidditch game, none of the players have shadows on the ground. (01:16:20)
Revealing mistake: After being dropped by the troll in the girls' lavatory, Harry then scoots backwards on his backside and it is apparent that he is wearing knee pads under his pants. (01:11:40)
Revealing mistake: At the start of the overhead shot as the troll's club smashes the cubicles, while Hermione lies on the ground, the top beams of all the cubicle walls and the front door of the second cubicle are all visibly pre-broken before the club slams into them. (01:10:15)
Revealing mistake: During Madame Hooch's flying lesson, as Ron tries to get his broomstick to float up to his hand, Ron moves his head towards his right to be in perfect alignment with the handle of his broomstick, as it flies up to whack him in the head. (00:55:40)
Revealing mistake: At the end of the film, when Harry is leaving on the Hogwarts Express, and the overhead shot shows the train pulling away from the station you can clearly see that Hagrid is of normal height, as the train roof is much taller than he is. (02:23:40)
Revealing mistake: While sitting on the couch in the hut on the rock, Hagrid asks, "Did you ever make anything happen, anything you couldn't explain? When you were angry or scared?" In the shot when he's getting up off the couch, it is blatantly apparent that the fingers on his left hand are latex in this shot. The hands are visibly artificial in other shots as well. (00:15:30)
Revealing mistake: Has anyone else noticed that Ron's rat, while on the Hogwarts Express at the beginning, is at one point fake! When he is explaining his spell to Harry, it comes into shot and is completely still, it moves like it is a toy. (00:36:25)
Revealing mistake: Harry, Ron and Hermione are at Hagrid's hut asking him about the hooded man and the dragon egg. The background behind Hagrid, which is the hut, is really behind him, but when it cuts to Harry, Ron and Hermione it is very apparent that the kids were edited in with their background, which is the school. (01:50:45)
Revealing mistake: When the letters burst through the letter opening, which has been covered by a piece of wood, you can see that the piece of wood was pre-cut. (00:12:00)
Revealing mistake: When Harry and Hagrid are at Gringotts and are pulling up in the cart to Harry's vault, in the overhead shot you can see the various levels bellow them. In the next shot in the lower left corner you can see what appears to be blue screen just bellow the walking surface. (00:22:10)
Chosen answer: There are several reasons. First, the position is cursed, so there is little reason to give Snape the job when he will not last any longer than all the previous instructors. If Snape did become the DADA instructor, something could happen to him that could result in his being harmed, having to leave Hogwarts, or be otherwise incapacitated in some way; that would render him useless to Dumbledore as a double agent. Also, Dumbledore trusts Snape, but putting him in an environment where he is teaching about dark magic on a daily basis would be too tempting and emotionally compromising to someone who had been so easily seduced by the dark side. He could possibly relapse. It would be like having a recovering alcoholic work as a bartender. Of course, he does eventually become the DADA instructor, and lasted no longer than his predecessors.
raywest ★
In the movies it is never mentioned that DADA role was cursed by Voldemort.
This is true; though it doesn't say it's not either. With trying to fit 7 long books and years worth of pages of HP information in 2 and a half hours; as long as the movie doesn't say it's not cursed, with our knowledge, there is no problem with reporting that it is. Even directors of non-book movies do this all the time; leave background information out that helps explain things they just didn't have time so they explained it behind the scenes.